Accurate assessment of undrained shear strength (USS) for soft sensitive clays is a great concern in geotechnical engineering practice. This study applies novel data-driven extreme gradient boosting ...(XGBoost) and random forest (RF) ensemble learning methods for capturing the relationships between the USS and various basic soil parameters. Based on the soil data sets from TC304 database, a general approach is developed to predict the USS of soft clays using the two machine learning methods above, where five feature variables including the preconsolidation stress (PS), vertical effective stress (VES), liquid limit (LL), plastic limit (PL) and natural water content (W) are adopted. To reduce the dependence on the rule of thumb and inefficient brute-force search, the Bayesian optimization method is applied to determine the appropriate model hyper-parameters of both XGBoost and RF. The developed models are comprehensively compared with three comparison machine learning methods and two transformation models with respect to predictive accuracy and robustness under 5-fold cross-validation (CV). It is shown that XGBoost-based and RF-based methods outperform these approaches. Besides, the XGBoost-based model provides feature importance ranks, which makes it a promising tool in the prediction of geotechnical parameters and enhances the interpretability of model.
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•XGBoost and RF-based ELMs for predicting the undrained shear strength of soft clays.•Bayesian hyper-parameter optimization for determination of the hyper-parameters.•ELMs performance and transformation model comparison.•Feature relative importance ranked by the proposed XGBoost-based model.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
With the increasing demand for transportation infrastructure, the construction of urban tunnel systems linking different areas is indispensable. The deformation and the failure process during a ...tunnel excavation are essential concerns for geotechnical engineers. However, few studies have systematically investigated the effect of the ground loss ratio on tunnel deformation and the inequality between the ground loss ratio and the volume of the settlement trough. An experimental study using the transparent soil testing technique is performed herein for better visualization and digitization purposes. The three dimensional vertical and horizontal deformation patterns of a single tunnel are investigated for both the surface and the stratum right below considering different ground loss ratios. The relationship among the empirical constant of the settlement trough width, buried depth, depth–diameter ratio, and ground loss ratio is presented.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Safety, non-toxic, and degradable ammonium alginate with polyvinyl alcohol were selected as substrates for the preparation of AA/PVA hydrogel by simple co-blending and cyclic freeze-thaw methods. ...Curcumin as the model drug was encapsulated to obtain AA/PVA/Cur hydrogel. The resulting hydrogels were characterized using various techniques to confirm the success of preparation, including FTIR, SEM, XRD, TGA, and rheometer. In addition, multiple stimuli-responsive behaviors of hydrogels were studied in depth. For one thing, AA/PVA hydrogel showed dual response shape memory properties which could be fixed in a temporary shape in Ca
2+
or low temperature and followed recovery to the original shape with more than 90% recovery rate in Na
+
(Na
2
CO
3
and EDTA.2Na) or high temperature respectively, confirming that the hydrogels have ion- and temperature-responsive behaviors. For another, the drug-loaded hydrogel AA/PVA/Cur exhibited different drug release properties under different pH stimulation conditions, where curcumin could reach nearly 90% release under alkaline conditions after 6 h, whereas the release rate was only nearly 20% under acidic conditions. AA/PVA/Cur hydrogel had antibacterial and antioxidant effects, especially under alkaline conditions. Thereinto, the antibacterial rate of
Escherichia coli
and
Staphylococcus aureus
reached over 90%, respectively. Among the four antioxidant systems, up to 98.5%, ABTS radical scavenging rate was prominent. In conclusion, multiple stimulus-response properties of AA/PVA hydrogel exhibit a unique three-dimensional network structure capable of drug loading, combined with various properties such as good hydrophilicity, biocompatibility, biodegradability, non-cytotoxicity, and hemocompatibility, which have potential applications in medical and pharmaceutical fields.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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•Preparation of monodisperse nanogel by reflux precipitation polymerization.•Nanogel system can be used as slow-release carrier for active drugs.•Curcumin-loaded nanogel system with ...multiple stimulus-responsive release behaviors.•Curcumin-loaded nanogel system stabilizes antioxidant effects.•Multiple stimulus-responsive nanogel system is biocompatible.
Curcumin (Cur) is of interest due to its widely reported pharmacology, which is limited by its low water solubility and low bioavailability of clinical use. Here, we report the characterization and application of a multiple stimulus-responsive nanogel loaded with Cur. Sensitive P(AM-co-NIPAM) nanogels for pH, temperature, and reduction stimuli were prepared by reflux precipitation polymerization method using AM and NIPAM as raw materials. DLS and SEM analyses showed that the fabricated nanogels had a uniform size distribution with spherical and nucleated-shell structures. By adjusting the feeding amounts of reactive monomers, cross-linkers, and initiators, a series of monodisperse nanogels with different particle sizes could be obtained. The representative nanogels have different Cur-loaded behaviors at different temperatures, times, and initial concentrations of the drug, as well as a sensitive release to changes in pH, temperature, or reducing conditions. Cur-P(AM-co-NIPAM) nanogels showed superior antioxidant activity over the free Cur in vitro. Meanwhile, it inhibited LPS and H2O2-induced oxidative stress, which could effectively inhibit the cellular production of excessive reactive oxygen species and had a protective effect against LPS-induced cellular damage. This nanogel controlled release system significantly improved the safety limit of Cur without hemolytic behavior and had good cytocompatibility. The successful development of such Cur nanogels will lead to advanced materials that can be functionalized and optimized for the controlled delivery of small molecules or biomolecules for targeted therapeutic and biomedical applications.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•CQDs/Cur have been prepared in a green, economical and eco-friendly way, with good dispersion and solubility in water.•CQDs have good excitation wavelength dependence, salt ions stability and ...photobleaching resistance, and pH adjustability.•CQDs/Cur have stronger antioxidant capacity than free Cur.•CQDs/Cur retain the excellent antibacterial properties of curcumin.
Carbon quantum dots with good biocompatibility can be used as nanomaterial carriers to improve the bioavailability of curcumin. In this paper, green tea was used as raw material to provide a green synthesis method for preparing carbon dots nanoparticles, and Curcumin was loaded to prepare carbon quantum dots/Curcumin nanocomposites (CQDs/Cur). A series of characterization methods were used to study the morphology and chemical structure of composite nanoparticles. The tea carbon dots had the characteristics of excitation wavelength dependence, salt solution stability and light stability. Finally, the antioxidant activities of CQDs/Cur nanocomposites were investigated by DPPH, ABTS•+, hydroxyl radical, metal ion chelating and reducing power assays. The compound system not only improved the antioxidant performance of curcumin, but also retained the antibacterial activity of curcumin. These results suggested that tea carbon quantum dots loaded with curcumin had the potential to be developed as natural antioxidants and antibacterial agents.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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•The core-shellAunanorod@mesoporous-silica/curcuminnanocomplexes has been prepared.•AuNRs@Cur exhibited excellent singlet oxygen yield and transfer ability of light to heat.•AuNRs@Cur ...had significantly improved antibacterial abilities under light irradiation.•AuNRs@Cur showed excellent antibacterial effect with combined PDT and PTT effect.•AuNRs@Cur showed good biocompatibility.
Bacteria are becoming increasingly resistant to antibiotics because of their overuse. As a result, new therapies are urgently needed to replace traditional antibiotic therapies. Photodynamic therapy and photothermal therapy are considered to be effective sterilization methods instead of antibiotics to resist drug-resistant pathogens. In this work, silica-coated gold nanorods with photothermal conversion effects were employed as photothermal carriers, and curcumin was selected as photosensitizer, to form PTT/PDT dual-mode antibacterial nanocomposites (AuNRs@Cur). Comparing with their counterparts Cur and AuNRs, AuNRs@Cur exhibited higher singlet oxygen yield and photothermal conversion efficiency, which greatly improved the utilization rate of photosensitizer and consequently effectively enhanced the photoinactivation effect of bacteria. The inhibition rate of AuNRs@Cur on S. aureus and E. coli under 405 and 808 nm dual irradiation was higher than that of Cur or PDT alone. The changes of bacterial membrane structure were revealed by scanning electron microscopy (SEM) and confocal fluorescence imaging. The reactive oxygen species and thermal energy generated by dual-wavelength (405 + 808 nm) laser irradiation can cause the destruction of bacterial outer membrane structure, resulting in bacterial death. In addition, the cytotoxicity and hemolytic activity of AuNRs@Cur were negligible. AuNRs@Cur nanocomposites proved thatphotodynamic-photothermal synergistic treatment can greatly improve the bactericidal effect. Therefore, construction of AuNRs@Cur provides a new idea for pathogen infection caused by drug-resistant bacteria, and provides relevant nano-carrier experience for follow-up drugs.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Photodynamic therapy and photothermal therapy provide new ways to combat antibiotic resistance. In this research, methylene blue (MB) as an effective photosensitizer was conjugated with carbon ...quantum dots (CQDs), the composite product not only possessed good antibacterial properties against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) due to excellent singlet oxygen (1O2) production rate and light heat transfer performance, but also showed good biocompatibility. Combined with 808 nm and 660 nm laser irradiation, the minimum bactericidal concentration of CQDs‐MB towards S. aureus and E. coli was 5 μm. Therefore, this study provides a potential candidate material based on CQDs for clinical applications.
Carbon quantum dots (CQDs) were synthesized by hydrothermal method. The CQDs‐methylene blue (MB) were obtained by combining the CQDs with MB. The compound had photothermal therapy and photodynamic therapy effects under light conditions and provided antibacterial effects.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Developing bifunctional innovative food packaging for maintaining and monitoring food freshness is crucial for food safety. Here, we prepared tannic acid cinnamaldehyde nanoemulsions through ...self-assembly and ionic cross-linking between the natural emulsifiers tannic acid and cinnamaldehyde, and were incorporated into chitosan as a protective outer layer. Sodium alginate anchored with alizarin was employed as the sensing inner layer. A pH-sensitive bilayer film integrating real-time monitoring and maintenance of food fresh food freshness was designed using layer-by-layer assembly (LBL) technology. The prepared bilayer film exhibited 100 % UV protection, >99 % antimicrobial effect, and 94.86 % and 97.91 % clearance rates for DPPH and ABTS free radicals, respectively. In addition, the bilayer film exhibited high biosafety and sensitive, reversible, and rapid response to pH/NH3. Shrimp preservation experiments showed that the smart bilayer film could effectively slow down the growth of microorganisms on the surface of shrimp, extend the freshness period of shrimp, and could monitor the freshness of shrimp in real-time through color changes. In conclusion, the prepared SL-CCT bilayer film has excellent potential for food preservation and freshness monitoring, providing a new perspective for design and development of multifunctional smart food packaging films.
•Ultrasonically triggered preparation of emulsions by self-assembly of tannins with cinnamaldehyde without emulsifiers.•pH-sensitive sodium alginate-anchored chymotrypsin for sensitive and rapid monitoring of shrimp freshness.•The bilayer film has excellent antimicrobial properties and stability, effectively extending the shelf life of the shrimp.•Outstanding biosafety with bilayer membranes.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
To fulfill the current need for intelligent active food packaging. This study incorporated the curcumin inclusion complexes (CUR-CD) into chitosan/polyvinyl alcohol polymer to develop a new ...intelligent active film. The structures of films were analyzed by Fourier-transform infrared (FT-IR), scanning electron microscope (SEM), and so on. The CP-Cur150 film displays exceptional mechanical properties, water vapor barrier, and UV blocking capabilities as demonstrated by physical analysis. The CP-Cur150 film exhibited free radical scavenging rates on 2,2-diazo-di-3-ethylbenzothiazolin-6-sulfonic (ABTS) (98 %) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) (87 %). Additionally, it showed inhibitory effects on Gram-positive bacteria (Staphylococcus aureus) and Gram-negative bacteria (Escherichia coli), reducing live colony counts by approximately 2.7 and 1.3 Log10 CFU/mL, respectively. The films were used to monitor the shrimp's freshness in real time. With the spoilage of shrimp, the film exhibited clear color fluctuations, from light yellow to red. In addition, the evaluation of the impact of films on pork pH, total volatile basic nitrogen, and total bacterial counts demonstrated that the CP-Cur150 film displayed the most significant effectiveness in preserving freshness, thereby extending the shelf life of pork.
•Successful preparation of curcumin inclusion complexes to improve the solubility of curcumin in water•Curcumin inclusion complexes can be uniformly dispersed in chitosan/polyvinyl alcohol film matrices.•The intelligent active films in this study had antioxidant, antimicrobial and pH-indicating properties.•The intelligent active films in this study can be used for real-time monitoring of shrimp freshness and pork preservation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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